Sluice box and amalgamation concentrator



1937- A. MOORHEAD SLUICE BOX AND AMALGAMATION CONCENTRATOR Filed Feb. 29, 1936 2 Sheets-Sheet 1 Patented Nov. 23, 1937 STATES PATENT OFFlCE SLUICE BOX AND AMALGAMATION CONCENTRATOR Claims.

This invention relates to improvements in devices for recovering gold and pertains particularly to an improved structure whereby fine gold is ob tained by amalgamation.

The primary object of the present invention is to provide an improved structure which may be employed to recover fine gold from sources from which it has been heretofore impossible to obtain the same, the recovery being made by effecting the flow of the gold bearing sand or other aggregate over rifiie plates having a surface coating of mercury which amalgamates with the gold particles and thus holds the same back while allowing the other heavy particles to pass on.

A further object of the invention is to provide a novel structure wherein the gold bearing material is distributed through acircular trough from which it is allowed to flow over several centrally converging mercury covered copper plates, from which plates the material passes on to a fabric screen and into a second receiver where any fine particles of gold which may have escaped the mercury plates will be trapped in the fabric or obtained by settlement A still further object of the invention is to provide an improved sluice structure in which there are no moving parts which can become clogged with the gold bearing material and which may, therefore, be operated continuously without re- 36 quiring cleaning or repair.

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawings forming part of this specification, with 35 the understanding, however, that the invention is not confined to any strict conformity with the showing of the drawings but may be changed or modified so long as such changes or modifications mark no material departure from the salient fea- 40 tures of the invention as expressed in the appended claims.

In the drawings: 7

Figure 1 is a view in top plan of the gold mining pan or sluice structure embodying the present in- 45 vention.

Figure 2 is a sectional view taken on the line 2-2 of Figure 1.

Figure 3 is a sectional view taken on the line 3-3 of Figure 1.

59 Figure 4 is a section taken on the line 4-4 of Figure 1.

Figure 5 is a sectional view through a modified form of a mercury coated copper plate.

Referring now more particularly to the draw- 55 ings, wherein like numerals of reference designate corresponding parts throughout the several views, the numeral I designates what may be termed a multiple sluice box into which the gold bearing sand or the tailings from a stamp mill, Rolls or Huntington mill may be discharged. This mul- 5 tiple sluice box is preferably of circular design as illustrated and may be constructed of Wood, metal, or any other suitable material, the illustrations here made being intended to indicate wood. construction throughout, except where 9 otherwise specified. This box comprises a circular outer wall 2 which extends upwardly from the outer edge of a bottom 3 which slopes toward the opening 4 which is formed at its center. Disposed inwardly of the outer wall 2 is an inner wall 15 5 which is in spaced relation with the wall 2 thus forming a circular trough 6.

The inner wall 5 is provided with a plurality of openings land extending inwardly toward the open center 4 from each of the openings 1 is a 2 pair of chute walls 8 which terminate at the edge of the opening 4 and form a chuteway 9 leading from each opening 7 to the central opening of the box. At the upper end of each of the converging chutes 9 is a screen guard H] which covers the opening 1 and in front of this guard is a vertical shiftable gate H, which is maintained in position by any suitable means, such, for example, as the guide cleats l2 which are vertically disposed against the inner sides of the chute walls 8 in spaced relation with the inner trough wall 5.

The bottom of each of the converging chutes 9 has a floor extending throughout its length which consists of a copper plate i3 and the surface of each of these plates is provided with a coating or covering 14 of mercury when the ore separator is in use.

Covering the opening 2 below the bottom of the box I is a receiver which comprises a vertical wall l5 and a bottom I 6 of screen Wire. This 40 constitutes a receiving pan for the ore bearing material which flows over the plates l3 of the chutes 9. The surface of the screen bottom I6 is covered over an area adjacent the wall [5 with a woven fabric ll of the nature of burlap. On to this fabric the material falls from the" chutes 9 before it reaches the screen proper.

Leading through the outer wall 2 of the multiple sluice box structure is an end of a lead-in sluice box !8 by means of which the ore bearing material is washed into the multiple sluice box I. This sluice I8 is provided upon its bottom IS with a plurality of copper plates 20, each of which is covered by a screen 2| which is held down by the transverse cleats or riflle bars 22.

These plates 20 are also covered with mercury when the ore concentrator is in use. The discharge end of the sluice I8 is tipped slightly to one side, as illustrated in Figure 4, so that the water flowing therefrom into the circular trough 6 will be discharged in one direction around the trough and will thus effect a complete circulation of the water and ore bearing material. In addition, as shown in Figure 1, the sluice l8 discharges against the wall 5 between two of the gate controlled openings 1.

The multiple sluice box I rests upon a settling pan or box 23 into which the screened tray underlying the opening t discharges. This box has an outlet 24 which is disposed at an elevation above the bottom of the box and which discharges into a tailings chute or trough 25. The fioor of the tailings trough is also provided with copper plates 28 which are covered by screens 21 and held down by transversely disposed cleats 28 and thesecopper plates 26 are also covered with mercury when the device is in operation.

While the structure described may be made up of wood, as previously stated, it may be desirable to construct the same of sheet metal, in which case the floor or bottom of the multiple sluice box may be provided with openings in which the copper plates are set. In Figure 5, the numeral 29 indicates a portion of a metal bottom for the multiple sluice box, in which an opening 30 is formed which is bordered at each side by the upstanding sluice wall 3| corresponding with the walls 8 of the box structure I. These metal walls 3| may be welded or otherwise suitably secured in the opening 33 to the bottom 29 and they have positioned therebetween along theirlower edges the copper chute plate 32 which has downturned edges 33 for welding at'the lower edges of the walls 30. The numeral 34 designates theme'rcury surfacing or coating for the copper plate 32.

In the operation of the present combination isluice box and amalgamation concentrator, the Upper end of the inclined lead-in sluice trough I8 is disposed to receive stream water bearing the sand or other material with which the fine gold particles are mixed. This gold bearing material is allowed to flow down over the plates 20 and the rifile bars '22 into the circulating trough 6 of the 'multiple sluice box I. The material then flows throughthe circular trough .6 through the screened openings i toward the central discharge opening of the trough, the gold particles which may settle to the bottom in passing over the mercury coated floor plates of the chutes 9, being picked up through amalgamation with the mercury with which the plates are covered. Any -gold particles which may escape amalgamation with the mercury on the plates [3 will be washed ofi onto the burlap or cloth covering of the re- Tceiving pan screen l6 and some of these particles will be caught by the burlap. The material then flows through the screen l6 into the settling box 23 and the water carrying the material flows out of the box by way of the tailings trough 25. Any of the gold particles which fail to be caught before reaching the box 23 and which fail to settle to the bottom of this box must then pass over the mercury covered copper plates "26 before being discharged from the device and these will be picked up by the copper plates. The screen coverings for the plates serve to trap the "gold particles and further assist in holding them against movement through the troughs.

In'addition to receiving gold bearing stream sand and other material directly into the sluice trough I 8 it will be apparent that the device may be used in association with a stamp mill and the tailings from such mill discharged into the upper end of the trough 18 while allowing water from any suitable source to flow into the trough so as to wet the tailings and carry the same down through the course described. By this means the extra fine or flour golds which would ordinarily be lost through the discarding of the stamp mill tailings, will be extracted therefrom.

The multiple sluice box l when in use is arranged so that one side of the bottom will be at a slightly higher elevation than the other.

The side which is elevated is that toward which the bulk of the 'gold bearing material is discharged from the sluice l8. By tipping the discharge end of the sluice [8 so as to direct the bulk of the material toward one side of the sluice box I and by raising the side of the sluice box toward which the material Y is discharged the water and material borne thereby will be caused to eddy around the circular trough and thus a portion thereof will pass over each of the mercury coated copper plates. g V I While the foregoing description has been confined to the use of the amalgamator for recovering gold it is, of course, to be understood that it may be employed in the recovery of other precious or desirable metals, if found desirable.

1. A sluice box structure comprising means forming a circular trough into which gold hearing material-is washed, said troughhaving inner and outer walls and a bottom and said inner wall having a plurality of openings therethrough, a plurality of chutes leading from said openings toward the central partof the circular area defined by the trough, a receiver at the center of said area into which the chutes discharge, and an amalgamation plate forming the bottom for each of said inwardly directed chutes'over which the said material passes. I

2, In a sluice box structuraja circular trough having inner, outer and bottom walls, said inner wall having aplurality of openings therethrough, a plurality of centrally converging chutes each leading from an opening of said inner wall, a screen bottom'receiving pan into which saidinwardly converging chutes discharge, each of said chutes having a mercury surfaced floor, gate means controlling the flow of material through each of said 'openings, and a fabric material overlying the screen bottom'of said pan adjacent the'discharge ends of said chutes, the said chutes discharging their material upon the fabric.

3. A sluicebox structure of the character described comprising a plurality'of sluice troughs arranged with their discharge ends in converging relation, a screened receiving'pan common to the converging ends of said troughsga' copper'plate forming a bottom for each'of said tr oughs,jmercury covering the top surface 'of eachpf said copper plates, trough means for supplyinggold bearing material tosaid plurality of troughs, a sluice tr'ough'having one'endarranged for discharge into said trough means,;a mercurycoate'd plate di'sposedin the bottom'of said: last sluice trough, a settling box disposed beneath said screened pan, an outlet trough for said settling box, and a mercury coveredcopper'plate disposed in the bottom of said outlettrough. H w 4. An improved sluice box comprising a cirpu f e a lrd re sed b ttom. av n an e ing 'at th e center, an upstanding wall surrounding said bottom, an inner wall in spaced relation with said surrounding wall forming a circular trough, a plurality of screened openings formed in said inner wall, a plurality of radially inwardly extending chutes leading from said screened openings to the center opening of said bottom, a settling box disposed beneath said bottom and having said opening discharging downwardly thereinto, said bottom opening having a screen fabric covering, a burlap covering over the said screen fabric in proximity to said chutes, the central portion of said screen fabric being uncovered, a mercury covered copper plate forming the bottom of each of said chutes, means for conducting ore carrying water into the circular trough, and a carrying ofif trough leading from said settling box at an elevation above the bottom thereof.

5. In a sluice box structure of the character described, a plurality of sluice troughs arranged with their discharge ends in converging relation, a screened receiving pan common to the converging ends of said troughs into which the troughs discharge, an amalgamation plate forming a bottom for each of said troughs, trough means for supplying gold bearing material to said plurality of troughs, a fabric material overlying a portion of the screen of said receiving pan, said troughs discharging onto said fabric material, a sluice trough having one end arranged for discharge into the trough means, and a settling box disposed beneath said screened pan and having a discharge outlet disposed at an elevation above the bottom thereof.

ALBERT L. MOORHEAD. 

